HELP!! How to use public key which inside the Cert to encrypt

[Steven Lo (HKBU)]

HELP!!
I think this is very simple question. But I have no idea.
I have received a certificate. And I want to encrypt some bytes with the public key inside this certificate.
I try to several function such as cryptGetpublickey() but fail (error).

please tell me what function should I use

THANK YOU
THANK YOU